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1.
《Ethology, Ecology and Evolution》2012,24(1):51-61
The hypothesis that the elaborated genitalia of male insects serve to improve insemination success were tested using the ground beetle Carabus insulicola. To enhance variation in genital size, the genital hooks of experimental males were cut, and these males were then mated with virgin females. Logistic regression showed that the length of the male genital hook affected insemination success. Males with a shorter genital hook tended not to deposit spermatophores at the proper site, and failed to transfer sperm into the spermatheca. Therefore, the male genital hook serves to increase insemination success by depositing a spermatophore at the site where sperm are likely to be transferred. The duration of copulation and post-copulatory guarding may also be explained by these determinants. Stepwise regressions indicated that the occurrence of ejaculation, and the location of the spermatophore determined the duration of copulation and post-copulatory guarding, respectively. 相似文献
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3.
【目的】为丰富赤眼蜂Trichogramma的种类资源,明确野外新采集的一种赤眼蜂的种类,探明该赤眼蜂所感染Wolbachia的类型。【方法】采用挂米蛾Corcyra cephalonica卵卡法在华南农业大学树木园诱集到两批赤眼蜂,通过形态鉴定和PCR扩增ITS2序列并测序分析的分子鉴定手段对野外采集的赤眼蜂材料进行种类鉴定;通过PCR扩增Wolbachia的外膜蛋白基因(wsp)序列,检测赤眼蜂体内Wolbachia的感染情况;通过PCR扩增wsp序列和多位点序列分型(multilocus sequence typing, MLST)对检测到的赤眼蜂体内的Wolbachia进行同源性分析。【结果】所诱集到的两批赤眼蜂均被鉴定为安荔赤眼蜂Trichogramma oleae Voegelé & Pointel,体内Wolbachia的感染率达100%。该Wolbachia株系与安荔赤眼蜂(前南斯拉夫品系)、短管赤眼蜂T. pretiosum(乌拉圭品系)以及T. deion(荷兰品系)体内Wolbachia亲缘关系较近,属于B超组Sib亚组,对应MLST序列型为ST486。【结论】安荔赤眼蜂T. oleae为中国野外首次发现,是完全感染Wolbachia的产雌孤雌生殖品系。本研究为害虫生物防治提供了一种新的天敌种类资源,并为进一步探明Wolbachia与赤眼蜂的互作提供了研究材料。 相似文献
4.
Tomasz Wilhelm Pyrcz Dorota Lachowska-Cierlik Keith Richard Willmott Artur Mrozek Oscar Mahecha-Jiménez Christer Fåhraeus Pierre Boyer Sebastián Martín Marianne Espeland 《Systematic Entomology》2023,48(1):163-177
A new genus of Neotropical Satyrinae butterflies, Viloriodes Pyrcz & Espeland gen. n. is described in the Pedaliodes Butler complex comprising 11–13 genera and more than 400 species. Support for the new genus is provided by a phylogenetic analysis based on target enrichment (TE) data including 618 nuclear loci with a total of 248,940 nucleotides, and the mitochondrial gene cytochrome oxidase subunit 1 (COI). Five species, whose DNA sequences were obtained by TE during this study, form a strongly supported clade sister to the large clade comprising Pedaliodes and four other genera. Complementary COI analysis confirms the monophyly of Viloriodes gen. n., with the above five plus eight other species clustering in highly supported clades in both Bayesian Inference and Maximum Likelihood analyses, and a TE + COI concatenated tree. Based on molecular and morphological data, 30 species are assigned to Viloriodes gen. n. The new genus can be recognized by a set of subtle morphological characteristics of colour patterns and male and female genitalia. An analysis of divergence times indicates that Viloriodes gen. n. and Steromapedaliodes Forster separated around 5.9 Mya. Viloriodes gen. n. has a wider geographic distribution than any other genus of the Pedaliodes complex, being found from central Mexico to northern Argentina and to the Guyana Shield, typically occurring at lower elevations than Pedaliodes. 相似文献
5.
The fatty acid composition of the stomach contents, adipose tissue, and perinephric fat of Polynesian rats (Rattus exulans Peale), from the Tokelau Is indicated that the dietary fat consisted mainly, if not exclusively, of coconut oil. Lower ratios of lauric : myristic acids were found in the depot fats of the Polynesian rats than in the dietary coconut oil. These results were consistent with chain elongation of lauric to myristic acid after ingestion, as previously reported in rats and other mammals. 相似文献
6.
Mohammad Kamil USMANI 《Entomological Research》2009,39(1):1-35
A comparative study of male and female genitalia was carried out in thirty‐seven Libyan species representing twenty genera of the family Acrididae. An attempt has been made to describe and illustrate the different structures, namely, epiphallus, aedeagus, subgenital plate, supra‐anal plate and cerci of the male, and spermatheca, ovipositor, subgenital plate, supra‐anal plate and cerci of the female, in Acridids, with an aim to discover their significance in order to make the identification of genera and species, together with other generic characters, more perfect and convenient. Distinct family characters are shield or bridge‐shaped condition of epiphallus; presence or absence of dorso‐lateral appendices, oval sclerites and lophi on epiphallus; divided, undivided or flexured condition of aedeagus; presence or absence of gonopore process on aedeagus; condition of apical and pre‐apical diverticula of spermatheca; presence or absence of glandular pouches of Cornstock and Kellog on female subgenital plate; and rudimentary or well developed condition of egg‐guide. Stable characters for separating the subfamilies are taken to be presence or absence of ancorae on epiphallus, long or short condition of aedeagal sclerites; elongate, slender or short and broad condition of ovipositor valves: presence or absence of Jannone's organs and setae on posterior margin of female subgenital plate; and shape of diverticula of spermatheca. Useful generic characters are shape of male subgenital plate, supra‐anal plate and cerci, broad or narrow condition of bridge, presence or absence of branch of bridge connecting lophi with bridge of epiphallus; mono‐, bi‐ or tri‐lobate condition of lophi of epiphallus, length and upcurved or downcurved condition of apical valve of aedeagus, shape of posterior margin of female subgenital plate, presence of setae on the whole posterior margin or confined to lateral margins only; and toothed, tuberculate or smooth condition of ovipositor valves, length of the lateral apodeme in relation to the dorsal valves. Specific characters are shape of egg‐guide of female subgenital plate, shape of ovipositor valves and apical tips, shape of male supra‐anal plate and cerci, size of anterior and posterior lobes of lophi of epiphallus, size and shape of ancorae, shape of apical valves of aedeagus; and size of apical and pre‐apical diverticula and presence of protuberance on pre‐apical diverticulum. 相似文献
7.
Abstract Based on an examination of the type specimens of all the known species of the genus Pamborus Latrielle (Coleoptera, Carabidae) four new Australian species are recognised and are described as: P. euopacus sp. n., P. moorei sp. n., P. monteithi sp. n and P. cooloolensis sp. n. In addition, Pamborus viridis Gory, P. opacus Géhin and P. subtropicus Darlington are also redescribed based on the type material and lectotypes are designated for the first two species. 相似文献
8.
Marshal C. Hedin 《Evolution; international journal of organic evolution》1997,51(6):1929-1945
This paper summarizes the results of an initial effort to reconstruct the speciational history of cave spiders (Nesticus) from the southern Appalachian Mountains of eastern North America. The Appalachian Nesticus fauna includes a large series of about 30 species distributed across islandlike cave and montane habitats. Many of the species are geographically restricted; all of the species are found in allopatry. Observed patterns of morphological variation and biogeographic evidence suggest that species diversification in this lineage may have occurred recently, perhaps in response to Pleistocene climatic fluctuations. To address questions about the spatial and temporal dynamics of Nesticus speciation, while accounting for potential phylogenetic difficulties, I have gathered nuclear and mitochondrial DNA sequences for a sample of individuals from 81 populations representing 28 Nesticus species. Analyses of these data indicate that considerable genetic divergence exists within and among currently recognized morphological species. Consistent with relatively deep species divergences, most of which likely predate the Pleistocene, is a prevailing pattern of phylogenetic concordance between taxonomic species and monophyletic gene tree lineages. The few deviations from monophyly detected can be tentatively attributed to a peripatric mode of speciation. Although species limits as inferred by the molecular data are generally concordant with patterns of morphological continuity and discontinuity in genitalia, there is evidence to suggest that cryptic phylogenetic lineages exist within some morphologically continuous units. This observation, in combination with the general depth of species lineages, makes any argument about rapid evolution in Nesticus genitalic characteristics unnecessary. 相似文献
9.
The genus Mystrium is revised for the Malagasy region. Six species, Mystrium barrybresslerisp. n., Mystrium labyrinthsp. n., Mystrium equessp. n., Mystrium mirrorsp. n., Mystrium shadowsp. n., and Mystrium janovitzisp. n. are described as new. Two existing names, Mystrium fallax Forel and Mystrium stadelmanni Forel, are synonymized with Mystrium voeltzkowi Forel and Mystrium mysticum Roger, respectively. All recognized species, including species outside of the Malagasy region, are assigned to one of the three newly proposed species groups. The associations between existing names and males are reexamined, and males of eight of the ten Malagasy species are described or redescribed. The taxonomic history of Mystrium highlights the importance of using unique identifiers when designating type specimens and the use of deposited vouchers in phylogenetic and ecological studies. Keys to species for workers, queens, and males are provided. Furthermore, a neotype for Mystrium mysticum is designated, as well as lectotypes for Mystrium camillae Emery, Mystrium rogeri Forel, Mystrium fallax Forel, Mystrium oberthueri Forel, Mystrium stadelmanni Forel, and Mystrium voeltzkowi Forel. Stigmatomma gingivale (Brown) is reassigned to Amblyopone as comb. rev. and Amblyopone awa Xu & Chu, Amblyopone kangba Xu & Chu, Amblyopone meiliana Xu & Chu, and Amblyopone zomae Xu & Chu are transferred to the genus Stigmatomma as comb. n. 相似文献
10.
ANDREAS TADLER 《Zoological Journal of the Linnean Society》1996,118(1):83-97
The functional anatomy of the genitalia of Nemasoma varicorne (Nemasomatidae), Brachyiulus lusitanus, Unciger foehdus and Cylindroiulus boleti (Julidae) was investigated by shock freezing of animals in copula followed by serial semithin sectioning of the engaged genitalia. The species show conspicuous differences in the functional mechanism of their genitalia. In M varicorne and B. lusitanus the vulvae remain within the vulval sac during copulation while in U.foetidus and C. boleti parts of the gonopods (promerite and mesomerite) form clasper-like structures that pull out the vulvae from the vulval sacs. With the exception of C. boleti all investigated species have a 'central funnel' on the vulva which leads into the receptaculum seminis. The sperm-transferring part of the male gonopods (solenomerite) is introduced into this funnel during copulation. In B. lusitanus and C. boleti a projection of the posterior gonopods (end-projection, brachite) fits into a slit anterior to the openings of the receptacula. The results are discussed with regard to sexual selection theory and a hypothesis is proposed that explains the evolutionary change of millipede genitalia by a combination of female choice and sperm competition phenomena. 相似文献